Posted by culverpratt on
URL: https://www.es-forum.com/shielding-a-computer-keyboard-mouse-tp1543473p1543527.html

Thanks for replying, Marc and Garth -- I have been unable to read
messages until I finally came back to work today (because of the
wiring problems which make my own computer/keyboard/mouse put out a
high electric field, I have not been plugging it in). I'll try to get
time "between work" to write some.

My computer does have a 3-prong cord -- it is the house wiring (1910-
built
house) that is screwed up and so nothing is ever actually grounded,
apparently. Outlet testers show a variety of results from different
receptacles in the house, but this appears to be meaningless since
when I tried plugging a long grounded orange
extension cord in to other places in the house that were
supposedly "ok", I still got the high electric field from the
entire computer and any peripherals plugged into it. Same thing from
anything else in the house as well as the metal plumbing
fixtures (not so wide a field though). I have 2 outlet testers, and
some outlets show contradictory results on one or the other tester.
So I am staying away from
anything plugged in, as well as some walls that put out a high
electric field for 4-5 feet, and some ceilings when the lights are
switched on (crawling on the floor is okay). I turn on the water
with a rubber spatula. What a hilarious sitcom this would make.

QUESTION: I don't suppose it would work to attach a grounding wire to
a metal screw on the backplate of the computer and take that out the
window to a grounding rod? Seems unlikely because it would still be
attached to the rest of the ungrounded system, right?










--- In [hidden email], Garth Hitchens <garth@...> wrote:
>
> Agreed. It is not neccesary to have high electric fields from
the  
> keyboard/mouse, especially if you are using a desktop computer.  
> Grounding your computer case should cure the problem completely.  
If  
> your computer has a 3 prong (grounded) plug, it should be already  
> grounded, so there could be a problem with the grounding in the  
> outlet or the grounding inside the computer. If your computer
only  
> has a 2 prong plug (rare for a desktop), I would suggest running a  
> grounding wire from a metal screw on the computer case to a known  
> electrical ground (sometimes the center screw of the outlet cover  
> works well). Also, with a 2 prong plug, you might try first in
the  
> computer "the other way" an see if that helps.
>
> I had/still have some problems because laptops are usually not  
> connected through 3 prong plugs, and therefore often have high
stray  
> electric fields, whereas desktop computers usually are grounded
and  
> don't usually have those stray electric fields.
>
> Garth
>
> On Feb 16, 2007, at 9:46 AM, Marc Martin wrote:
>
> >> It appears that anything plugged into the computer, including
> >> headphones, mic, etc. all carry the field full-strength,
including